Question

oxygen atoms tend to gain 2 electrons to form oxide anions. (a) what is the charge on a oxide anion? etextbook and media (b) what is the average atomic mass of a oxygen atom in atomic mass units?

Explanation:

Step1: Recall electron - charge relationship

Each electron has a charge of - 1.

Step2: Calculate oxide - anion charge

Since oxygen gains 2 electrons, the charge is $(-1)\times2=- 2$.

Step3: Recall oxygen atomic - mass value

The average atomic mass of an oxygen atom is approximately 16 atomic mass units.

Answer:

(a) - 2
(b) 16